Cup grinding wheel assembly

ABSTRACT

A cup grinding wheel assembly includes an abrasive wheel having a frustoconical central opening therethrough and a mating frustoconical shaped nut secured to the cup grinding wheel through a bayonet coupling. The grinding assembly is positioned on a spindle of a grinding tool.

United States Patent Walters 1 June 25, 1974 1 CUP GRINDING WHEELASSEMBLY [76] Inventor: Klemens C. Walters, Logan Rd.,

R.D. No. 1, Box 218, Gibsonia, Pa. 15044 [22] Filed: May 3, 1973 [21]App]. No.: 356,935

[52] US. Cl. 51/168, 51/209 R [51 Int. Cl B24b 45/00 [58] Field ofSearch 51/168, 206 R, 209 R; 279/93, 103

[56] References Cited UNITED STATES PATENTS 2,266,604 12/1941 Murphy279/93 2,278,301 3/1942 Bauer 51/209 R 2,486,078 10/1949 Tocci-Guilbert51/168 2,806,331 9/1957 Hoye 51/168 3,716,951 2/1973 Walters 51/209 RFOREIGN PATENTS OR APPLICATIONS 87,300 6/1896 Germany 51/209 R PrimaryExaminer-Al Lawrence Smith Assistant Examinerl(. J Ramsey Attorney,Agent, or FirmWebb, Burden, Robinson & Webb [57] ABSTRACT A cup grindingwheel assembly includes an abrasive wheel having a frustoconical centralopening therethrough and a mating frustoconical shaped nut secured tothe cup grinding wheel through a bayonet coupling. The grinding assemblyis positioned on a spindle of a grinding tool.

3 Claims, 5 Drawing Figures CUP GRINDING WHEEL ASSEMBLY FIELD OF THEINVENTION My invention relates to grinding equipment and, moreparticularly, to cup grinding wheels.

DESCRIPTION OF THE PRIOR ART In my US. Pat. No. 3,716,951, I disclosed acup grinding wheel and frustoconical shaped nut therefor whicheliminated the integral metal bushing and the resultant costly practiceof discarding the unused abrasive portion which included the metalbushing. The frustoconical shaped nut contains tool engaging slots alongthe upper surface which are engageable by a special tool for tighteningthe assembly on a spindle.

My above described grinding assembly has proven effective but can befurther improved by connecting the nut to the grinding wheel through abayonet connection to form an integral unit. This improvement eliminatesany slippage associated with the frustoconical shaped nut since it isheld in place through its connection to the grinding wheel. In addition,the need for special wrenches is eliminated since my improved grindingassembly can be now positioned on the spindle by hand. In addition, thenut is locked to the cup grinding wheel by a simple hand manipulation.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross section taken alongthe center line of my grinding assembly;

FIG. 2 is an isometric of the nut;

FIG. 3 is a section through the bayonet slot of the cup grinding wheel;

FIG. 4 is a broken isometric of the bayonet slot; and

FIG. 5 is a cross section taken along the center line of a cup grindingwheel forming another embodiment of my invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT The grinding assembly, generallydesignated 10, includes an abrasive cup wheel 12 and a securing nut 14attached thereto for securing the grinding assembly to a threadedspindle 16 of a grinding tool, not shown, FIG. 1. The abrasive cupgrinding wheel 12 has a central opening 18 extending completelytherethrough. Central opening 18 is defined by interior wall 20 and isfrustoconical shaped. The outer periphery of cup grinding wheel 12 canbe defined by any of the cup grinding wheel shapes and the flaredsidewalls of FIG. 1 are exemplary. The actual grinding is conductedalong the forward or top surface of the cup grinding wheel 12.

The nut 14 is also frustoconical shaped and the shape of the nut 14includes the same angulation as wall of opening 18, FIG. 2. However, thenut 14 is dimensioned so that its smallest cross section or base islarger than the smallest cross section of the opening 18, FIG. 2. Nut 14easily fits into the opening 18 but cannot extend through or reach thesmall base. Nut 18 includes oppositely directed lugs or bayonets 21 and22 which are spaced 180 apart and are positioned slightly upward fromthe small base of the nut 14.

The cup grinding wheel 12 includes two bayonet slots 23 along theconical wall 20 which defines the central opening 18, FIG. 1. Thesebayonet slots 23 extend vertically through the wheel 12 and include anentry section 27 and a holding section 29 separated by a shoulder 28,FIGS. 3 and 4. Shoulder 28 and holding section 29 accommodate the lugs21 and 22 in the assembled position.

My grinding assembly is assembled by placing the nut 14 into the centralopening 18 so that the lugs 21 and 22 slip into the entry section 27 ofbayonet slot 23. The nut is then given a slight turn so that the lugs 21and 22 are moved into the holding section 29 beneath shoulder 28 of thebayonet slots 23. The grinding assembly is then placed on the spindleand merely rotated by hand so that the threaded hole 17 in the nutthreadably engages the spindle 16 of the grinding tool. The nut 14forces the cup grinding wheel 12 against the adapter plate 24 which canbe an integral part of the grinding tool. Because of the dimensions ofthe nut 14 relative to the opening 18 in the cup grinding wheel 12, aspace 25 is formed between the bottom of the nut 14 and the adapterplate 24, FIG. 1. 7

After use the remaining grinding assembly 10 is normally removed bymerely striking the wheel 12 against a hard rigid object such as theworkpiece being ground. The nut 14 is easily removed by hand through aslight turning movement and is then ready for reassembly with anothercup grinding wheel.

The cup grinding wheel 12 can also be formed with a thin metal backingplate 30 secured thereto, FIG. 5. This backing plate is molded intomechanical securement with wheel 12 by means of a plurality of keys 32punched outwardly from plate 30 at an angle of about and which extendupwardly into the abrasive wheel 12. Plate 30 includes a central opening31 which loosely accommodates the spindle of a grinding tool. Theinclusion of plate 30 in the grinding assembly avoids the necessity ofan adapter plate since the plate 30 can be tightened against thestandard grinding tool fitting which accommodates the metal bushings ofthe prior art.

I claim:

1. A grinding assembly for securement on a grinding tool including a cupgrinding wheel having a frustoconical central opening defined by aninner wall and extending therethrough and a nut, the sidewall of whichis at the same angulation as said inner wall, the nut dimensioned so asto be wholly retained within the central opening and having at least onelug extending outwardly from the sidewall, said inner wall having atleast one bayonet slot recessed therein to accommodate each lug and forma bayonet coupling therebetween.

2. The assembly of claim 1, each bayonet slot defined by a verticallyextending receiving section and an adjacent holding section including ashoulder which accommodates the lug in a locked position.

3. The assembly of claim 1, said grinding wheel including an aperturedbottom plate having a plurality of integral keys extending into andmechanically secured to said grinding wheel.

1. A grinding assembly for securement on a grinding tool including a cupgrinding wheel having a frustoconical central opening defined by aninner wall and extending therethrough and a nut, the sidewall of whichis at the same angulation as said inner wall, the nut dimensioned so asto be wholly retained within the central opening and having at least onelug extending outwardly from the sidewall, said inner wall having atleast one bayonet slot recessed therein to accommodate each lug and forma bayonet coupling therebetween.
 2. The assembly of claim 1, eachbayonet slot defined by a vertically extending receiving section and anadjacent holding section including a shoulder which accommodates the lugin a locked position.
 3. The assembly of claim 1, said grinding wheelincluding an apertured bottom plate having a plurality of integral keysextending into and mechanically secured to said grinding wheel.